A post mortem examination revealed that Mr Lyall died of multiple injuries caused by a number of weapons.

It is believed that a number of people were involved in the attack, which is thought to have been connected to drugs.

Ali, who is known as 'Madman,' 'Johnny' and 'Gulaid' has a distinctive gold front tooth, which detectives suspect may have been removed or covered with a veneer to help disguise his appearance while he is on the run.

He may also have stubble or a beard.

In addition to his links to Sheffield, he also has connections to Lancashire, Merseyside, Manchester, Milton Keynes, Lincolnshire and Cleveland.